Device for protecting induction-motors and the like.



E. 0. SCHWEITZER. DEVICE FOR PROTECTING moucnou MOTORS AND THE LIKE.

APPLICATION FILED AUG-3.1912.

Patented Oct. 19, 1915.

2 SHEETS-SHEETI COLUMBIA PLANOGRAPH 1:0u WASHINGTON. D. c

E. 0. SCHWEITZER.

DEVICE FOR PROTECTING INDUCTION MOTORS AND THE LIKE.

APPLICATION FILED Aue.3,1912.

1 1 57,05 1. Patentd Oct, 19, 1915.

2 SHEETS-SHEET 2.

COLUMBIA PLANOGRAPH C0., WASHINGTON, D C.

EDMUND 0. SCHWEITZER, or CHICAGO, ILLINoIs.

DEVICE EQR PRQTECTIN'G INDUCTION-MOTORS AND THE LIKE.

2 Specification of Letters Patent I Patented O61]. 1915.

Application filed August 3, 191 2. Serial No. 713,129.

To all whom it may concern}:

- Be it known that I, EDMUND O. SOIIWEIT- ZER, a citizen of the UnitedStates, residing at Chicago, in the county of Cook and State ofIllinois, have invented a Certain new and usefullmprovementin Devicesfor Protecting Induction-Motors and the like, of

which the followingis a full, clear, concise, and exact description,reference being had to the accompanying drawings, forming a part of thisspecification:

My invention relates to devices for protecting induction motors or otherdevices from improper connection or arrangement of the leads or linesystem.

One specific use of the invention is inconnection with induction-motorsfor elevators. In such apparatus the improper conwires of a polyphasenection of the motor would obviously cause very damagingresults bystarting the elevator in the wrong direction. I

Prominent objects of the invention are to provide a simple, practical,and'efficient device of this character; to reduce the cost of making thesame; to make the device stable and not liable to derangement; to makeunnecessary the attendance of an expert after installation and torequire the attention of the central station after the device has'operated before it canbe put into service again.

In the device for carrying out my invention herein set forth I arrangeto automatically control the circuit so as to open the same or otherwisecontrol it upon the improper connection of the: leads or circuitconnectors. This is, conveniently done by means'of-a solenoidarrangement ordinarily inoperative when theleads are properly connectedbut operative to control the circuit when the leads are'improperlyconnected.

In the accompanying drawings, Figure 1 is afront elevation of a deviceembodying my invention; Fig. 2 is a side elevation of the same; Fig. 3is a detail of a part of the apparatus; Fig. 4 is an elevation of theupper part of the apparatus as shown in Fig.

1, showing the same in an operative condition; Fig. 5 is a plan view ofthe device; Fig. 6 is a diagram view of the circuit arrangement.

The device shown comprises a base or support 1, intended for verticalarrangement and conveniently in the form of a flat board or plateprovided with apertures 2--2 and end to end a pair of solenoids 3, 4which are conveniently held in vertical position by supports 5, 6, inthe form of plates secured to the board 1 by screws 7-7. Within thecentral bore of these solenoids is arranged an iron core 8 which iscommon to both so lenoids and has a length aboutequal to the length ofone solenoid. This core is free to move vertically in the hollow bore ofthe two solenoids, being as a convenient I arrangement mounted upon aspindle or plunger 9 whose lower end fits loosely in the bore 10 of aplug llfitted into the lower end of the lower solenoid 4,the plug 11being constructed with a pin 12 extending down from its lower end andengaged by set nuts 1313 arranged on opposite sides of a post 14 securedto the supporting board 1. The pin or rod 12 is screw threaded so as topermit adjustment of the plug 11 which forms a stop and guide. While thecore 8 can be of any suitable construction, it is desirably by athreaded sleeve 15 secured as by soldering to the spindle 9, and a metalplunger cap 16' and a nut 17, the cap or washer 16 being fitted downover the threaded sleeve 15 and held in place against. the upper end ofthe fiber tube 8 by the threaded nut 17 Above the core 8 is anupper stopand guide 18 desirably made of iron and held in place by screws 18*.Above this is a spiral spring 19 and above the latter a metal 'stop' andcatch 20 firmly secured to the spindle 9 as by threading the spindle andputting set nuts 2121 on opposite sides of the disklike stop and catch20. Near the upper end of the spindle 9 is mounted an insulated contactdevice 22 conveniently in the form of a carbon disk 23 having a largecentral bore containing a hub or bushing 24 of insulating material, asfor example fiber, mounted upon the threaded end of the spindle 9.Insulating material washers 25 and 26 are arranged above and below thecarbon disk 23 respectively, and metal washers 27 and 28 are arrangedabove and below the washers 25 and 26 respectively, with threaded nuts29 and 30 above and below'the latter. A

metal terminal member or lug 31 is arranged below the disk 23. andbetween the same and the insulating disk 26, being in contact with thecarbon disk 23.

Two contact devices 32 and 33 (Figs. 1 and 2) are mounted upon theupright support 1, being conveniently suspended from metal spring strips32 and 35 respectively, which latter are mounted upon posts 36 and 37respectively secured to the supporting board 1. The contacts 32 and 33are located above the insulated contact disk 22 so that when the spindle9 rises sufficiently the contact 22 will strike against and make contactwith the contacts 32 and 33. A swinging lever arm 38 is. pivoted uponthe support 1 at 39 and is held down by a spring 40 so that when thespindle 9 rises'suiiiciently to cause the con-tact 22 to come into,contacts 32 and 3,3 the lever arm 38 will be swung over as shown in Fig.l, so that its end slips in under the washer 20 and engages the same tohold the spindle in an elevated position, The contact lug or terminal 31is connected; by a flexible conductor 40 with a binding post 41-1 on thesupport 1, and this binding post ll is in turn connected by a conductor42 with one of the leads or line wires 43, of a 3-phase system as shownin the diagram, Fig. 6. at are connected with the leads or line wires45,44: and 4-3 by wires 46, 47 and 48 respectively. The contacts 32 and33 are connected with the lines wires and 44 respectively by conductorsQ9 and 50. A high resistance 51 is shown included in the conductor 48Fuses 52 are shown included in the line wires 43, at and 1-5 and theconnection of the protecting device is shown between said fuses and themotor or other load. Thus it will be seen that when the line wires areconnected in proper manner to the device the movable magnetic core ormember will remain. in a lowered position because of the direction ofthe lines of the field of force, but when the connections are improperlymade. or reversed, the magnetic member The solenoids 3 and' will risedue to a reversal of the direction of the lines of force of the magneticfield and cause the contact disk 22 to make contact with the members 32,and 33, thereby short circuiting the line wires and causing the fuses 52to blow. This will protect the motor or other device to be protected andwill require attention from the central station to insert new fusesbefore the circuit can be put into operation again.

It will be understood that changes and modifications can be made withoutdeparting from the spirit of the invention.

hat I claim is:

1. A device of the class specified comprising vertically arrangedmagnetic coils adapted for connection in a polyphase circuit, avertically movable core member having a core influenced by said coils soas to shift said core member vertically and upwardly upon a reversal ofphase in said coils, circuit connections arranged to be closed upon anupward movement of said core member, and a spring controlled latchadapted to engage and hold said core member when elevated to an extentto close the circuit.

2. A reverse phase relay comprising in combination, a solenoid, amagnetic member mounted within said solenoid adapted to move axiallythereof, a spindle connected to said member, a contact carried by saidspindle, a disk also carried by said spindle, a pivoted arm, and aspring throwing said arm against the edge of said disk in the normalposition of said member, said arm being adapted toengage the face ofsaid disk upon the movement of said member in one direction.

In witness whereof, I hereunto subscribe my name this 1st day of August,A. D. 1912.

EDMUND O. SCHXVE'ITZER.

\Vitnesses:

A. L. JONES, HAZ L. Jones.

Copies of this patent may be obtained for fiveicents each. byaddressjngthe Commissioner of Patents. Washington, I). C,'--

